The International Electrotechnical Commission (IEC), is the authority for world standards in electrical and electronics engineering. This present dictionary is the second edition of a dictionary which was first published by the Commission in 1983, entitled the IEC Multilingual Dictionary of Electricity . The title of this second edition reflects both the ever-increasing role of electronics in the activities of the Commission and the inclusion of terms relating to telecommunications. Volumes 3, 4 and 5 (index volumes) of this dictionary can each be used together with volume 2 or volume 1, volume 1 being especially intended for the French user, because of the definitions in French. All the index volumes refer to the English and French equivalents. In addition to providing a unique multilingual reference work, this dictionary is intended to facilitate understanding between electrical engineers of all countries and assist in eliminating a certain laxity in technical language, the source of numerous misunderstandings, costly in both time and money.